408-7527
Twin Leaf PC Board Edge Connectors
3
of 5Rev
A
Tyco Electronics Corporation
The contact must NOT cross the centerline of the
housing or contact damage may result.
3. Grasp the wire directly behind the contact
insulation barrel, and push the contact straight into
the cavity until it bottoms with an audible click.
4. Pull back lightly on the wire to be sure the
locking lance has locked in the cavity. Refer to
Figure 3.
3.4. Extraction
Extraction Tool 91073 is designed for removing
contacts from these connectors. Insert the releasing
tip into the FRONT of the cavity between the contact
and outer wall. Hold the tool against the connector
and depress the extraction handle. Remove the tool
and pull the contact out of the REAR of the cavity.
Refer to Instruction Sheet 408–7529 packaged with
the extraction tool for specific extraction procedures.
4. DUMMY CONTACTS
(Figure 3)
Dummy contacts are pre–crimped standard contacts
designed for use in double–sided pc board
applications. These contacts provide additional
mechanical pressure for partially loaded connectors,
and are inserted and extracted the same as standard
contacts. Dummy contacts should be placed in each
empty cavity opposite a standard working contact.
5. RETAINING SPRINGS
Retaining springs are designed for use in single–sided
pc board applications. They are inserted in the
unused side of the connector to provide and balance
the necessary board retention capabilities.
The recommended ratio for balanced retention is one
retaining spring to six contacts. The minimum number
of springs which should be used is one for every
seven contact positions.
1. Align the short end of the retaining spring with
the FRONT of the contact cavity.
2. Push the spring straight in until the short end
snaps into place behind the cavity ridge. See
Figure 4.
To extract a retaining spring, select one of the
following methods.
1. Insert a jewelers screwdriver into the REAR of a
cavity between the spring and center wall of the
connector. Depress the short end of the spring,
and push the retaining spring out the FRONT of
the connector.
2. Use Extraction Tool 91073 (contact extraction
tool). Insert releasing tip into the REAR of the
cavity between the spring and center wall of the
connector. Hold the tool against the connector and
depress the extraction handle. Remove the tool
and pull the retaining spring out the FRONT of the
cavity.
Figure 4
Cross-Section View of Housing
Retaining Spring Cavity Ridge
Short End of SpringFront of Connector
6. KEYING PLUGS
Connectors can be polarized with inter–contact keying
plugs that fit into slots between contact cavities, or
with on–contact keying plugs that fit into empty dual
contact cavities (a dual position) in the connector. See
Figure 5.
To insert an inter–contact keying plug, align the
beveled corners with the “V” notches of an upper and
lower rib on the FRONT of the connector. Insert the
plug straight into the connector until it bottoms.
To insert an on–contact keying plug, align it with
empty dual contact cavities on the FRONT of the
connector. Insert the plug straight into the connector
until the locking tabs snap over the BACK edge of the
connector.
A slot must be cut in the pc board to accept the
inter–contact or on–contact keying plug. Note that the
slot for the inter–contact plug must be located
between the circuit pads of the pc board, and the slot
for the on–contact plug must be located on the circuit
pad area of the pc board.
7. PANEL CUTOUT
Connectors that have mounting ears with or without
threaded inserts are designed for panel mounting.
The connector mounting location (FRONT or BACK)
must be determined before making the panel cutout.
FRONT mounting requires the use of a “C”
dimension, while BACK mounting requires a “D”
dimension. Refer to Figure 6. Note that the cutout for
BACK mounting will be larger than the cutout for
FRONT mounting.
CAUTION
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